More workers shifting from part-time to full-time jobs helped halt poverty’s expansion, but 15 percent of Americans continued to be counted as poor last year, according to U.S. Census Bureau figures released Wednesday.

The 46.2 million Americans living in poverty in 2011 was only slightly lower than the 2010 record, and would have been worse had there not been a decline in poverty in the suburbs, among immigrants who are not citizens and in the American South.

“It looks like there’s a big shift from part-time to full-time” work that helped lift those groups out of poverty, said David Johnson, chief of the Census Bureau’s housing and economic statistics division.

As the presidential contenders battle to win over the middle-class, the annual poverty statistics provide a glimpse at how America’s worst-off are faring.

Although the poverty rate didn’t rise, the median household income for all Americans declined 1.5 percent to $50,100 in 2011. That was an 8.1 percent decline from 2007, before the recession began, and 8.9 percent lower than the 1999 peak.

To be classified as poor in 2011, a family of two adults and two children would have had to make less than $22,811.

Some economists had predicted Wednesday’s annual report would show the poverty rate hitting its highest level since 1965, when President Lyndon Johnson announced his war on poverty. The fact that the numbers instead leveled off after three consecutive years of increase was a relief to some.

Still, the persistent poverty is troubling: the 15 percent poverty rate ties with 2010 as the highest since 1993 and one of the highest since the government began measuring poverty.

“Even if the economy was rebounding, I don’t think the official poverty statistics show it that much,” said Ann Stevens, an economics professor who directs the UC Davis Center for Poverty Research.

Unemployment insurance gives many down-on-their-luck Americans enough income to stay above the poverty line, but Stevens said the official poverty measurements don’t count food stamps, housing assistance and other programs that help people survive but don’t give them cash income.

“They’re likely to be used to say, look, the war on poverty isn’t working,” Stevens said of the latest numbers. “We know these programs do have benefits, they just don’t show up in these basic statistics.”

Among those looking for help this week was Martinez resident Jennifer Catalano, who came to the food pantry at Concord’s Monument Crisis Center with her daughter to pick up a once-a-month package of fresh produce, milk and cereal. Catalano and her husband own a home and he works as a drywall finisher, but the high cost of fuel and food keeps the family looking for food relief where they can find it.

“There’s some people who are way below me, and some people way above,” she said.

It was a diverse group in age and background that pulled up to the nonprofit pantry on Tuesday morning. Vietnamese immigrant Vang Van Mac lost a 12-year job at a dental supply company earlier this year, his first time out of work since he landed in the United States three decades ago. Joan Dougherty, 73, a former flight attendant, also lost a job this summer teaching watercoloring at an Orinda school, and wheeled herself into the pantry for the second time in two months.

At first, “I was embarrassed about getting help,” she said.

The poverty rate is lowest for people 65 and older, at 8.7 percent, largely because most qualify for Social Security payments. It is highest for children, with 1 out of every 5 living below the poverty line.

Poverty rates for African Americans and Latinos are double that of whites, but more Latinos rose out of poverty between 2010 and 2011, according to the estimates that come from the Census Bureau’s annual American Community Survey. The rate of Latino poverty dropped to 25.3 percent from 26.5 percent.